Researchers from the Massachusetts Institute of Technology and the Albert Einstein College of Medicine have recently discovered an elusive family of viruses that have escaped scientific analysis due to their characteristics. This previously unknown family of viruses thriving in the world’s marine habitats may help shed some light on how microorganisms maintain the ocean’s ecology, and may play an important role in understanding the human microbiome, as reported by a new study published in Nature on January 24, 2018.

• The researchers collected daily water samples off the Massachusetts coast for three months. Viruses found in the samples were incubated for two weeks in cultures of Vibrionaceae, a common family of marine bacteria.
• For the analysis, the scientists randomly selected more than 200 viruses that successfully infected and multiplied in the Vibrionaceae bacteria. Out of these viruses, 18 were found to belong to a new family of small, non-tailed dsDNA (double-stranded DNA) viruses, which the researchers named Autolykiviridae.
• In experiments involving more than 300 strains of Vibrionaceae bacteria, the researches found that the Autolykiviridae viruses preyed on many more strains of Vibrionaceae than the tailed viruses in the water samples.
• This suggests that viruses related to Autolykiviridae may be key players in the predator-prey balance in marine ecosystems as they can infect many diverse groups of ocean bacteria, and may even prey on other currently unidentified bacterial groups.
• The researchers believe that the presence of Autolykiviridae-like viruses is not limited to the oceans, as they have found related viral sequences in the gut microbiome.

This significant finding may give way to further studies to determine how these related viruses may influence microbial communities in the human gut or how they may relate to health.

Journal Reference:

Kauffman KM, Hussain FA, Yang J, Arevalo P, Brown JM, Chang WK, Vaninsberghe D, Elsherbini J, Sharma RS, Cutler MB, et al. A MAJOR LINEAGE OF NON-TAILED DSDNA VIRUSES AS UNRECOGNIZED KILLERS OF MARINE BACTERIA. Nature. 2018;554(7690):118–122. DOI: 10.1038/nature25474